This invention relates to the weighing of vehicles and to the measuring of vehicle engine power. The background of the invention relating to the weighing of vehicles will be described first followed by the background of the invention relating to measuring vehicle engine power.
Vehicles are conventionally weighed on weighbridges. These are large, expensive and complicated pieces of machinery and are essentially fixedly located.
Enacted and threatened legislation regarding total weight of vehicles and prescribing substantial fines for overweight condition has given rise to numerous suggestions for portable, less complicated, less bulky and less expensive forms of weighbridge. In such, for example, vehicular wheel axle weights are measured and summed to find the total weight. The idea is for the vehicle operator, not having access to a weighbridge, to be able to check that the vehicle is not overloaded and that it is within the law.
However, these suggestions of individual wheel or axle weight measurements involve time consuming operations involving placing the vehicle on the equipment one wheel or axle at a time. Such operations bring their own inaccuracies as well.
The present invention provides a method of and apparatus for weighing vehicles (particularly, but by no means exclusively, of road transport vehicles) which takes little time and which is always available when required.
With respect to measuring vehicle engine power, the power output of an engine can be bench-measured to give a brake horsepower figure which can be related to engine speed. This however may bear little relationship to the power of the engine in actual driving conditions and is in any event not useful for monitoring engine performance under actual driving conditions when performance-related parameters may change, such for example as ambient temperature, fuel mixture, spark plug timing (in petrol engines) and so on.